Association between Endometrial Polyps and Chronic Endometritis: Is It Time for a Paradigm Shift in the Pathophysiology of Endometrial Polyps in Pre-Menopausal Women? Results of a Systematic Review and Meta-Analysis

Plasma Cells as the Key Players of IVF Failure? Unlocking the Enigma of Infertility and In Vitro Fertilization Failure in the Light of Uterine Inflammation

There is an interplay between plasma cells, endometritis, and infertility, particularly in the context of in vitro fertilization (IVF) failure. This narrative literature review explains the pathophysiology of endometritis, detailing the involvement of various immune cells, cytokines, and chemokines in the regulation of inflammatory responses within the uterine endometrium. Here, we discuss the physiological role of plasma cells in immunity and their detection as markers of chronic endometritis, a disease associated with reproductive disorders. Our study also highlights the importance of CD138 immunohistochemical staining in the diagnosis of chronic endometritis, emphasizing the presence of plasma cells in endometrial tissue and its association with infertility and recurrent implantation failure. Of particular interest are the proposed diagnostic criteria for chronic endometritis based on the presence of plasma cells and studies that suggest a threshold for diagnosing this condition. We highlight the importance of examining the regenerative potential of endometrial stem cells in the treatment of infertility related to endometrial disorders.

Prevalence of chronic endometritis in infertile women undergoing hysteroscopy and its association with intrauterine abnormalities: A Cross-Sectional study

OBJECTIVE

Chronic endometritis (CE) is an inflammatory condition with several different risk factors. We aimed to examine whether intrauterine abnormalities, such as endometrial polyps, submucosal myomas, intrauterine adhesions, or a septate uterus, were associated with an increased likelihood of developing chronic endometritis.

METHODS

A cross-sectional study was conducted on 335 infertile women who underwent hysteroscopy surgery at the Ayatollah Taleghani Hospital Infertility Center, affiliated by Shahid Beheshti University of Medical Sciences, in 2022. All participants in the study underwent hysteroscopic surgery, which allowed for direct visualization of the intrauterine cavity, and endometrial biopsies were taken for further analysis. To characterize endometritis, plasma cell infiltration was assessed. Patients with ≥5 plasma cells observed in 10 high-power fields were defined as having chronic endometritis.

RESULTS

Endometritis was observed in 51.3% of the patients, totaling 172 individuals. Logistic regression analysis revealed that patients with endometrial polyps had 5.2 times higher odds of developing endometritis compared to patients without polyps (95% CI = 2.9, 9.2) (p-value <0.001). Similarly, patients with intrauterine adhesions had a significant increase in the odds of endometritis (OR = 4.6, 95% CI = 2.1, 10.1) (p-value <0.001).

CONCLUSIONS

Treatment or removal of endometrial abnormalities through hysteroscopic procedures may help to reduce the risk of chronic endometritis and improve fertility outcomes. Further research is necessary.

Impact of Hysteroscopic Polypectomy on IVF Outcomes in Women with Unexplained Infertility

Objective: To assess the effect of hysteroscopic polypectomy on the in vitro fertilization (IVF) results in infertile women with at least one prior negative IVF outcome. Methods: This retrospective cohort study included women who had attended the "2nd Department of Obstetrics and Gynecology of the National and Kapodistrian University of Athens" and "Iaso" Maternity Hospital from October 2019 to January 2023 for infertility treatment. The medical records of 345 women aged 18-45 years old without abnormal findings in hysterosalpingography (HSG) and with at least one previous failed IVF procedure were analyzed. The male factor was excluded, as well as a prior hysteroscopic removal of polyps. In 67 women, polyps were suspected during initial two-dimensional ultrasound (2D-US) examination. The final sample of the study comprised 40 patients, in which endometrial polyps were removed by hysteroscopy with the use of resectoscope. All patients underwent ovarian stimulation and IVF in the consecutive cycle using a short GnRh antagonist protocol. Main Results: After hysteroscopic polypectomy, 29 (72.5%) out of 40 patients had a positive pregnancy result: 26 (65%) clinical and 3 (7.5%) biochemical pregnancies were documented. There was a statistically significant difference between the number of clinical pregnancies before and after polypectomy (p < 0.001), as well as between the total number of pregnancies (p < 0.001). Secondary Results: Women with positive outcome were significantly younger and had significantly lower FSH levels (p < 0.007). They also had significantly higher AMH (p < 0.009) and peak estradiol levels (p < 0.013) and yielded more M II oocytes (p < 0.009) and embryos (p < 0.002). Conclusions: Hysteroscopic polypectomy in women with a suspected endometrial polyp using 2D ultrasound and a history of prior failed IVF attempt improves IVF outcomes in terms of the clinical and total number of pregnancies.

Chronic endometritis multiplies the recurrence risk of endometrial polyps after transcervical resection of endometrial polyps: a prospective study

BACKGROUND

To investigate the impact of chronic endometritis (CE) on the recurrence of endometrial polyps (EPs) in premenopausal women after transcervical resection of endometrial polyps (TCRP).

METHODS

This prospective study enrolled 507 women who underwent TCRP between January 1, 2022 and December 31, 2022. The patients were divided into a CE group (n = 133) and non-CE group (n = 374) based on the expression of CD138 in the endometrium. The EP recurrence rate at 1 year after TCRP was compared between the CE and non-CE groups and between groups with mild CE and severe CE. The impact of CD138 expression by resected EPs on EP recurrence also was investigated.

RESULTS

The EP recurrence rate at 1 year post-TCRP was higher in the CE group than in the non-CE group (25.6% vs. 10.4%) and also higher in the severe CE group than in the mild CE group (34.5% vs. 18.7%). Additionally, the EP recurrence rate was higher among patients with CD138-expressing EPs than among those with EPs lacking CD138 expression (30.5% vs. 6.5%). The odds ratio (OR) for EP recurrence in the CE cohort compared with the non-CE cohort was 3.10 (95% confidence interval [CI] 1.84-5.23) after adjustment for EP number and precautions against EP recurrence. The ORs for EP recurrence in patients with mild CE and severe CE were 2.21 (95%CI 1.11-4.40) and 4.32 (95%CI 2.26-8.26), respectively. Similarly, the OR for EP recurrence in cases with CD138-expressing EPs relative to cases with EPs lacking CD138 expression was 6.22 (95%CI 3.59-10.80) after adjustment for EP number and precautions against EP recurrence.

CONCLUSIONS

CE multiplied the recurrence rate of EPs in premenopausal women after TCRP, and this effect positively correlated with CE severity. CD138 expression by EPs also was associated with a higher risk for EP recurrence.

Endometrial microbiota alteration in female patients with endometrial polyps based on 16S rRNA gene sequencing analysis

Introduction

The potential role of the endometrial microbiota in the pathogenesis of endometrial polyps (EPs) warrants further investigation, given the current landscape of limited and inconclusive research findings. We aimed to explore the microecological characteristics of the uterine cavity in patients with EPs and investigate the potential of endometrial microbiota species as novel biomarkers for identifying EPs.

Methods

Endometrial samples were collected from 225 patients who underwent hysteroscopies, of whom 167 had EPs, whereas 58 had non- hyperproliferative endometrium status. The endometrial microbiota was assessed using 16S rRNA gene sequencing. We characterized the endometrial microbiota and identified microbial biomarkers for predicting EPs.

Results

The endometrial microbial diversity and composition were significantly different between the EP and control groups. Predictive functional analyses of the endometrial microbiota demonstrated significant alterations in pathways involved in sphingolipid metabolism, steroid hormone biosynthesis, and apoptosis between the two groups. Moreover, a classification model based on endometrial microbial ASV-based biomarkers along with the presence of abnormal uterine bleeding symptoms achieved powerful classification potential in identifying EPs in both the discovery and validation cohorts.

Conclusion

Our study indicates a potential association between altered endometrial microbiota and EPs. Endometrial microbiota-based biomarkers may prove valuable for the diagnosis of EPs.

Clinical trial registration

Chinese Clinical Trial Registry (ChiCTR2100052746).

Contrast Agent Reflux in Transvaginal 4-D Hysterosalpingo-Contrast Sonography: Influencing Factors and Coping Strategies

ABSTRACT

Transvaginal 4-D hysterosalpingo-contrast sonography (TV 4-D HyCoSy) plays an important role in the detection and diagnosis of clinical female infertility. The purposes of this study were to analyze the influencing factors of TV 4murD HyCoSy complicated with contrast agent reflux and to provide evidence for clinical diagnosis and treatment. Female patients diagnosed as infertility by transvaginal hysterosalpingography from January 2021 to December 2022 were included. The characteristics of patients with and without contrast agent reflux were evaluated. Pearson correlation and logistic regression were conducted to analyze the related factors affecting the occurrence of contrast reflux. A total of 416 patients undergoing TV 4-D HyCoSy were included, and the incidence of contrast agent reflux in patients undergoing TV 4-D HyCoSy was 38.94%. Pearson correlation analysis results indicated that history of uterine cavity operation ( r = 0.556), adenomyosis of uterus ( r = 0.584), examination on less than 5 days after menstruation ( r = 0.602), endometrial thickness ( r = 0.566), and endometrial polyps ( r = 0.575) are all correlated with contrast agent reflux in patients undergoing 4-D HyCoSy (all P < 0.05). Logistic regression analysis showed that history of uterine cavity operation (odds ratio [OR], 1.109; 95% confidence interval [CI], 1.012-1.872), adenomyosis of uterus (OR, 2.026; 95% CI, 1.864-2.425), examination on less than 5 days after menstruation (OR, 2.465; 95% CI, 2.118-2.851), endometrial thickness less than 6 mm (OR, 2.866; 95% CI, 2.095-2.957), and endometrial polyps (OR, 1.587; 95% CI, 1.137-1.744) were the influencing factors of contrast agent reflux in patients undergoing (all P < 0.05). The incidence of contrast agent reflux in TV 4-D HyCoSy is high, and there are many influencing factors. Clinical medical workers should take early measures based on these influencing factors to reduce the contrast agent reflux.

Primer on Female Infertility for the Reproductive Urologist

This review is intended to serve as an aid in decision-making and patient counseling for the reproductive urologist when female factor infertility is found concurrently with male factor infertility. This review pairs the pathophysiology of female infertility with its implications for the treatment of male infertility, which most commonly includes ovulatory disorders, tubal abnormalities, and uterine abnormalities. By gaining a deeper understanding of these factors, reproductive urologists can employ a tailored approach to managing male factor infertility, taking into account the female partner's specific medical history.

Pregnancy Rates after Hysteroscopic Endometrial Polypectomy versus Endometrial Curettage Polypectomy: A Retrospective Study

Background and Objectives: A relationship between endometrial polypectomy and in vitro fertilization (IVF) pregnancy outcomes has been reported; however, only a few studies have compared polyp removal techniques and pregnancy rates. We investigated whether different polypectomy techniques with endometrial curettage and hysteroscopic polypectomy for endometrial polyps affect subsequent pregnancy outcomes. Materials and Methods: Data from 434 patients who had undergone polypectomy for suspected endometrial polyps using transvaginal ultrasonography before embryo transfer in IVF at four institutions between January 2017 and December 2020 were retrospectively analyzed. Overall, there were 157 and 277 patients in the hysteroscopic (mean age: 35.0 years) and curettage (mean age: 37.3 years) groups, respectively. Single-blastocyst transfer cases were selected from both groups and age-matched to unify background factors. Results: In the single-blastocyst transfer cases, 148 (mean age: 35.0 years) and 196 (mean age: 35.9 years) were in the hysteroscopic and curettage groups, respectively, with the 148 cases matched by age. In these cases, the pregnancy rates for the first embryo transfer were 68.2% (odds ratio (OR): 2.14) and 51.4% (OR: 1.06) in the hysteroscopic and curettage groups, respectively; the resulting OR was 2.03. The pregnancy rates after up to the second transfer were 80.4% (OR: 4.10) and 68.2% (OR: 2.14) in the hysteroscopic and curettage groups, respectively, in which the OR was 1.91. The live birth rates were 66.2% (OR: 1.956) and 53.4% (OR: 1.15) in the hysteroscopic and curettage groups, respectively, in which the odds ratio was 1.71. These results show the effectiveness of hysteroscopic endometrial polypectomy compared to polypectomy with endometrial curettage. No significant difference was found regarding the miscarriage rates between the two groups. Conclusions: Hysteroscopic endometrial polypectomy resulted in a higher pregnancy rate in subsequent embryo transfer than polypectomy with endometrial curettage. Therefore, establishing a facility where polypectomy can be performed hysteroscopically is crucial.

High prevalence of chronic endometritis is associated with metabolic abnormality and reduced live birth rate among IVF women with non-uniform endometrial echogenicity

OBJECTIVE

To assess the prevalence of chronic endometritis (CE) among women with non-uniform endometrial echogenicity, and to evaluate the association between CE and metabolic characteristics as well as pregnancy outcomes in the subsequent frozen-thawed embryo transfer (FET) cycles.

DESIGN

Retrospective cohort study.

SETTING

University-based hospitals and an academic medical center.

PATIENTS

A total of 315 patients included in this research underwent hysteroscopy and endometrial biopsy before the first FET cycle after whole embryos freezing. Patients were divided into CE (histopathologic CE or hysteroscopic CE) and non-CE groups.

INTERVENTION(S)

Freeze-all strategy, hysteroscopy and endometrial biopsy.

MAIN OUTCOME MEASURES

Baseline and cycle characteristics, hysteroscopic, and histopathological profile, as well as pregnancy outcomes.

RESULTS

The prevalence of histopathologic CE and hysteroscopic CE were 78.1% and 34.9%, respectively. CE was associated with higher homocysteine level and BMI, independent of insulin response and dyslipidemia. High homocysteine level and BMI were risk factors for histopathologic CE (OR: 1.182; 95% CI: 1.01-1.384; p = .037) and hysteroscopic CE (OR: 1.117; 95% CI: 1.041-1.199; p = .002), respectively. Histopathologic CE was a risk factor for live birth (OR:2.167; 95% CI: 1.037-4.525; p = .04), and hysteroscopic CE was an independent risk factor for both live birth (OR: 4.239; 95% CI: 1.929-9.313; p = .001) and cumulative live birth (OR: 3.963; 95% CI: 1.875-8.376; p = .001).

CONCLUSIONS

Infertile women with non-uniform endometrial echogenicity have a high prevalence of CE which significantly reduces the live birth rate. Diagnosing CE by hysteroscopy is important to assess the cumulative probability of pregnancy in IVF patients.

Adverse impact of CD138+ cells in proliferative-phase endometrium on pregnancy outcomes in fresh IVF/ICSI cycles

To evaluate the impact of Syndecan-1 (CD138) in proliferative-phase endometrium on pregnancy outcomes in fresh in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) cycles. This retrospective cohort study contained 273 patients who underwent IVF/ICSI with fresh embryo transfer following an endometrial curettage from January 2020 to May 2022. Endometrial curettage was performed on all patients within 3 to 5 days following menstruation and endometrial tissue was acquired for detection of plasma cells by immunohistochemistry. Subsequent pregnancy outcomes of all cycles were traced and analyzed. A total of 149 patients became pregnant (i.e., pregnant group) in the fresh transfer IVF/ICSI cycles and 124 did not become pregnant (i.e., nonpregnant group). The number of CD138 + cells/ high-power field (HPF) of the nonpregnant group was significantly higher than the pregnant group (2.36 ± 4.24 vs 1.31 ± 3.41, P = .008). The cut off value of CD138 + cells/HPF was 2 by receiver operating characteristic curve analysis, with an area under the receiver operating characteristic curve of 0.572. Compared with the negative group (i.e., CD138 + cells/HPF < 2, n = 204), the positive group (i.e., CD138 + cells/HPF ≥ 2, n = 69) had a significantly lower clinical pregnancy rate (71.8% vs 40.6%, P < .001). The clinical pregnancy rate revealed a gradually decreasing trend with the increase in CD138 + cells. Proliferative-phase endometrial CD138 + cells may be an adverse indicator for pregnancy outcomes in fresh IVF/ICSI cycles, with a certain value in predicting non-pregnancy. Pregnancy outcome was poor when CD138 + cells/HPF ≥ 2 in the endometrium and may worsen with the increase in CD138 + cells.

Chronic Endometritis in Infertile Women: Impact of Untreated Disease, Plasma Cell Count and Antibiotic Therapy on IVF Outcome-A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to evaluate the impact of chronic endometritis (CE) and its therapy on in vitro fertilization (IVF) outcome. Additionally, we aim to investigate whether various degrees of CE severity may exert a different effect on IVF outcome. Ongoing-pregnancy rate/live-birth-rate (OPR/LBR), clinical-pregnancy rate (CPR), and miscarriage rate (MR) were calculated. A total number of 4145 patients (from ten studies) were included. Women with CE had lower OPR/LBR (OR 1.97, p = 0.02) and CPR (OR 2.28, p = 0.002) compared to those without CE. CE cure increased OPR/LBR (OR 5.33, p < 0.0001) and CPR (OR 3.64, p = 0.0001). IVF outcome was comparable between women with cured CE and those without CE (OPR/LBR, CPR and MR: p = ns). Women with severe CE had lower OPR/LBR (OR 0.43, p = 0.003) and CPR (OR 0.40, p = 0.0007) compared to those mild CE. Mild CE showed no influence on the IVF outcome as compared to women without CE (OPR/LBR, CPR and MR: p = ns). Based on this data analysis, CE significantly reduces OPR/LBR and CPR in women undergoing IVF. Importantly, CE resolution after antibiotic therapy may improves IVF outcome, leading to similar OPR/LBR and CPR as compared to unaffected patients. The negative effects of CE on IVF outcome may be restricted to severe disease, whereas mild CE may have no influence on IVF success.